Question

what would the graph look like if the same reaction were catalyzed by an enzyme? select the single best answer.

Explanation:

Enzymes are biological catalysts. Catalysts lower the activation energy of a reaction. In a reaction progress graph, the activation energy is the energy peak. So, the graph with the enzyme - catalyzed reaction will have a lower peak (lower activation energy) compared to the non - enzyme (uncatalyzed) reaction. The first graph shows the "With enzyme" curve having a lower peak than the "Without enzyme" curve, which is consistent with the role of enzymes in reducing activation energy. The second graph has the "With enzyme" curve with a higher peak (incorrect as enzymes lower activation energy), and the third graph has an incorrect starting point for the "With enzyme" reaction (the starting free energy of reactants should be the same for both catalyzed and uncatalyzed reactions).

Answer:

The first graph (the one where the "With enzyme" curve has a lower peak than the "Without enzyme" curve).